Water damage to windows is one of the biggest frustrations that property owners express to us at So Cal Squeegee Pros. It's a common problem with various causes and often people don't recognize the issue until the damage has already been done. After all, glass is more resistant to corrosion than most materials, so much so that we tend to think of it as being corrosion proof ( www.corrosion-doctors.org/)
Most people believe glass to be a perfectly smooth surface. I did. It wasn't until I began cleaning windows professionally in 2001 that I learned otherwise. My mentor explained to me that glass is actually porous. Glass manufacturers refer to it as lattice or honeycomb patterns, that under a microscope reveal peaks and potholes.
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"Lattice" pattern of glass seen under a microscope
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These microscopic potholes fill with contaminants and begin to react chemically with the glass, bonding them to the surface (www.corrosion-doctors.org/household/glass.htm/). The results are water spots, etching, and in more severe cases a solid haze on the glass.
This damage is categorized into two different phases or stages. There are many myths about removing water damage but if you want results it's better to stick with a regular cleaning schedule and the tried and true methods that professional window cleaners have used for years.
Causes and Prevention
How do you prevent water damage to windows? The simple answer is to prevent water from reaching the window. Unfortunately that is often more easily said than done. For example, most modern irrigation systems are set on automatic timers. While many of these timers can recognize rain and override the system, they aren't able to adjust for wind and other factors. The sprinklers come on, the home owner isn't home or otherwise not paying attention, and the wind blows the water from the sprinklers all over the windows. This goes on for weeks, months, sometimes even years. All the while minerals from the evaporated water remain behind, bonding to your glass.
Other times, well meaning homeowners inadvertently do the damage themselves. Many residents pressure wash or hose down their homes. It helps keep them looking nice and free dirt, webs, and other debris. Unfortunately, most do not remove the window screens or clean the windows afterward. All of the dirty water washes down and across the windows and screens leaving dirt and minerals behind.
To address this problem start by locating the source of the water. Many times it is as simple as a twisted sprinkler head. Twist it back and you're all set. Other times a different type of sprinkler may be more appropriate for that location, or perhaps irrigate at a time that is typically less windy such as early morning.
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| Help protect windows from water spots by using drip irrigation |
There are numerous landscape irrigation resources available online as well as at your local hardware store. You can also call a local landscaper. Many of these people are skilled tradesman and their talents reach far beyond mowing lawns. However, if the damage has already been done not to fear there are some proven treatment methods.
Types of Damage
Like metal, glass is subject to corrosion. These processes are caused by reactions between the surface of glass and gases in the atmosphere or the chemical composition of water. Glass is hydrophillic. That means it attracts and holds moisture. All glass has a molecular layer of moisture on the surface. When this layer increases because of humidity, rainfall, sprinklers, or or a well meaning home owner it contributes to the destruction of the surface of the glass. Even a single droplet of water on unprotected glass can produce visible damage (www.corrosion-doctors.org/household/glass/).
Stage one corrosion is aqueous corrosion, caused by moisture. lf water remains on glass for more than a moment chemical reactions can occur that cause damage or stains (Duffer). "An ion exchange occurs between sodium ions from the glass and hydrogen ions from the corrosion solution (www.corrosion-doctors.org/household/glass/, Duffer). The water leads to extraction or leaching of alkali ions from the glass. The result is a silica rich layer on the glass otherwise known as water spots.
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| Stage One (Aqueous) Corrosion |
Stage two corrosion is a process of destruction of the alkali leached layers if glass. Glass is resistant to most acids but highly susceptible to attack by alkaline materials, especially at pH concentrations higher than 9.0. If the reaction is allowed to continue, sometimes for more than just a moment, surface damage will become apparent and the glass may have a widespread iridescence or a dense translucent haze (Duffer). The result leads to dissolution of the glass surface (www.corrosion-doctors.org/household/glass/). "In each case the optic quality of the glass is destroyed even though the overall mechanical integrity of the glass is maintained (Duffer).
Treatment
Removal
There are several possible treatments for water damaged windows, and no doubt there are even more myths. A couple of the myths include scrubbing with vinegar or scraping the window with a common utility blade. More practical treatment options include 0000 steel wool, abrasive powders or pastes, and acid products.
Many people believe that common household vinegar will remove water spotting. The theory is that the acidity of the vinegar will breakdown the mineral deposits on the glass. The theory is good however, in real life one may spend days scrubbing with vinegar and never get satisfactory results. The acid in the vinegar simply isn't strong enough.
The next myth I often hear is that a common razor blade is best for removing water spots and damage from windows. Many people believe they can simply scrape the spots off the surface of the glass. A professional window scraper is a necessary and valuable tool to any respectable window cleaner however, it isn't the right tool for this job. As discussed, the problem is often more than just simple spotting or stage one aqueous damage and the mineral deposits have begun to etch the glass. Scraping the glass in these situations will usually only make problems worse. Generally speaking you will wind up with scratched glass and uneven streaks were the razor blade passed over the surface, but again you will not get satisfactory results.
The first practical product I will address is steel wool. If water spotting is light and has not bonded with the glass or if there are other types of debris on the surface they may come off with 0000 steel wool and some old fashioned elbow grease. However, it is very important to use only 0000 steel wool. More coarse products may scratch windows. In fact, it is a good practice to clean loose dirt and debris off of the windows before starting and periodically soaking your piece of 0000 steel wool with soapy window cleaning water as you work. This lubricates the wool and and helps avoid scratching your windows. This is the same reason you will see professional window cleaners soap a window before scraping it with a blade.
The next type products we will discuss are abrasive powders and pastes. These are usually pumice based, also require old fashioned elbow grease, and are good options for more heavy spotting. Again it's always a good idea to clean loose dirt and debris from the window first. Next, depending in the product, you will either mix it with water first or apply it directly to the window with a scrub pad. Again nothing too abrasive, you don't want to scratch the window. Scrub the window, rinse it, dry it, and see how it looks. If it's good, do your final scrub, Squeegee it, and your done. If you see results but it's not quite right you may want to try again. Sometimes it will take a few tries to remove it all. Remember I mentioned elbow grease.
If you see no results there are still options. My go to in these situations are acid based products. I don't recommend however that property owners attempt using these products as there can be several potential drawbacks. To begin with, acid can cause severe chemical burns, blindness, etc.
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| Acid burned hand |
Improper use can also burn glass and irreversibly ruin windows as well as discolor wood, stucco, and concrete.
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| Acid burned glass |
In addition, these products are relatively expensive. On the flip side, in the hands of an experienced and skilled window cleaner, acid can be a valuable tool and remove water damage when all other products have failed.
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| Heavily water damaged window before acid treatment |
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| Heavily water damaged window after acid treatment. |
Sealers
After the water damage has been removed and your windows are clean it is a good idea to treat effected windows with a professional grade glass sealer. Again, there are many good products on the market. It is important to remember though that no product forms an impenetrable barrier on your windows and it is still necessary to eliminate the source of water causing the damage as well as clean and seal your windows regularly.
Think of it like automobile wax. It's great for protecting your cars finish, but you wouldn't
Wax it, leave it parked in the path of your sprinklers for a year or two, and then expect it to come clean would you? You probably wouldn't get very good results. The more often you wash and wax the car the greater your chances of avoiding water damage to your paint. Likewise, if you keep a regular cleaning schedule and properly maintain your windows you greatly reduce the build up of contaminants on your window glass and frames. The result will be beautiful windows that can last for decades.
Written by Tim Bishop
So Cal Squeegee Pros
Hesperia, CA
(760) 297-7180
socalsqueegeepros@gmail.com
www.socalsqueegeepros.com
